Printing machine



y 23, 1951 G. P. REGAN, sR., ETAL 2,985,087

' PRINTING MACHINE Filed Aug. 18, 1959 2 Sheets-Sheet 1 INVENTORS GEORGEP. REGAN SR WILLIAM E. REGAN i BY 6,25%

s ATTORNEYS a G. P. REGAN, SR, EI'AL May 23, 1961 PRINTING MACHINE 2Sheets-Sheet 2 FIG.4

Filed Aug. 18, 1959 INVENTORS GE0RGE P. REGAN sR. WILLIAM E. REGAN BYM,Q8wm,w

ATTORNEYS United States Patent PRINTING MACHINE George P. Regan, Sr.,San Francisco, and William E.

Regan, Burlingame, Calif., assignors to Regan Industries, Inc.,Burlingame, Calif., a corporation of California Filed Aug. 18, 1959,Ser. No. 834,543

1 Claim. (Cl. 95-76) This invention relates generally to apparatus fortransferring a light image to a photosensitive surface and moreparticularly to such apparatus by which curved printing plates can beprinted with photographic images without distortion of register.

In the making of a commercial printing plate, the plate is first coatedwith a photosensitive resist material, exposed to a powerful light image(generally through a photographic negative), and then etched to removeunexposed portions of the metal surface to form an image in relief.

Procedures and apparatus satisfactory for flat plates are well known,but they are entirely unsuited for curved or semicylindrical plates suchas handled by the apparatus of the present invention. Specifically theprinting apparatus herein disclosed is adapted for use in the system formaking curved printing plates disclosed in copending application SerialNo. 834,037 filed August 17, 1959.

Generally, it is an object of the present invention to provide anapparatus and procedure for printing photographic images on curvedprinting plates, without distortion, and on a repetitive productionbasis.

Another object of the invention is to provide a machine for this purposein which the plates may be printed in perfect register with photographicnegatives, to provide printed plates of exceptional quality.

Another object of the invention is to provide such a machine which isrelatively simple in construction and operation.

Other objects and advantages of the invention will be apparent from thefollowing description and from the drawings in which:

Figure 1 is a perspective view of a printing machine embodying theinvention, showing the light source in open position;

Figure 2 is a view in side elevation of the machine of Figure 1;

Figure 3 is a sectional view with the light source in closed positiontaken along the lines 3-3 of Figure 2;

Figure 4 is a schematic view showing the manifold means by which forcesin suction are exerted about the periphery of the plate holder;

Figure 5 is a fragmentary view like Figure 1, showing the resilientpressure blanket removed from the face of the plate holder; and

Figure 6 is a view showing a detail of a preferred form of resilientblanket.

In general, the printing machine of the present invention employs acurved plate holder provided with means exerting forces in suction aboutits periphery. A flexible resilient blanket is adapted to overlay theplate holder in such manner that a curved printing plate can bepositioned between the holder and the blanket along with a superposedphotographic negative or other means forming a desired light image. Theflexible blanket has a transparent portion to permit exposure of theplate to a light source, which preferably is concentrically arrangedwith respect to the plate holder.

Referring to the drawings, 10 indicates a base frame for a curved,semicylindrical plate holder 12. As best seen in Figure 5, the uppersurface of the plate holder is recessed as at 14 to receive a curvedprinting plate 16 and negative 17. The outer periphery of the plateholder is constructed with a continuous groove 18 which is incommunication with conduit means 20 secured to the inner periphery ofthe plate holder by means of a series of apertures 22. The base frame 10supports a vacuum pump or other suitable source of suction 24 (Figures 1and 2) and means to operate the pump, such as the electric motor 26. Thepump 24 functions to exert forces in suction about the periphery of theplate holder 12 through the continuous groove 18. This is accomplishedby exhaust of gas through the flexible conduit 28 and through themanifold 30 (Figure 4) which communicates with the conduit 20.Preferably the manifold has branches 32 to distribute the suction forcesequally about the conduit 20. A separate branch 34 also communicateswith the surface of the plate through an aperture 36, for a purpose tobe later explained.

As best seen in Figures 1 and 5, a flexible resilient blanket is adaptedto overlay the plate holder 12. The blanket is secured at one edge tothe plate holder, for example, as at 42 in Figure 3. The opposite orfree edge of the blanket is preferably weighted (e. g. by the rod 43) sothat in the position of Figure 1 the blanket will assume a relaxedposition in concentric alignment with the plate 16. The blanket is alsoprovided with a transparent insert 44 of flexible plastic or othersuitable material. This insert is constructed to be in register with theplate 16 and to permit exposure of the plate to a light image.

During a printing operation, the suction exerted between the plateholder and the resilient blanket (through the groove 18 and aperture36), assures that the negative will be held in a position of desiredregister with the curved plate. Referring to Figure 3, suction exertedin the conduit 20 exhausts the air from the space between the blanketand plate holder through the apertures 22. Eventually, edge portions 41of the blanket 40 are sucked into the continuous groove 18 toeffectively seal the blanket against the plate holder. To insure aperfect registry it is also desirable to exhaust the air in the space 45about the periphery of the plate and negative. In the preferredembodiment illustated, this is accomplished by the separate exhaustaperture 36 in cooperation with a plurality of waffle-like protuberances48 provided on the interior of the blanket 40. As will be understood theprotuberances 48 provide passages 50 therebetween permitting removal ofsubstantially all the air surrounding the edges of the plate andnegative. The net result is that the negative is pulled tightly aboutthe curved plate with the elimination of creases or wrinkles which mightotherwise provide misalignment or undesired distortion.

The printing is preferably accomplished by means of a curved lightsource concentrically positioned with respect to the plate holder 12. Asillustrated in Figures 1 and 2, the light source is mounted in a frame62 pivotally mounted on the base frame 10 so as to be swingable from anopen position to a desired concentric position adjacent the plateholder. The frame 62 provides means for suitably mounting both the lightsource and a curved concentrically arranged reflector 66 spaced abovethe light source. Proper alignment of the frame 62 is obtained by thefixed pivots 68 and the resilient supports 70, provided on the baseframe 10. The construction just described has effect of concentratinglight uniformly on the curved surface of the plate, thereby insuring arapid even exposure of such surface.

The operation of the apparatus just described can be summarized asfollows: The flexible blanket 40 is removed from the surface of theplate holder 12, as in Figure 5, and a coated curved printing plate 16positioned within the recessed area 14 of the plate holder. The negative17'is then placed above the curved plate in a desired position ofregistry, and the blanket 40 moved to overlay the plate and negative, asin Figures 1 and 2. The pump 24 is now energized to exert a vacuum onthe manifold 36, causing suction to be exerted through the aperture 36and the apertures 22 cornunicating with the continuous groove 18. As aresult, the blanket 40 is sealed against the plate holder and free airexhausted from about the edges of the curved plate and negative toinsure that the latter is tightly held against the plate 16 in aposition of perfect registry. The light source ea is now swung to aconcentric position above the plate holder, making use of the handle orsupport 72. Upon energizing the light element for a desired interval,light of predetermined intensity is caused to penetrate the resilientblanket and the negative to expose the surface'of the plate. Uponswinging the light source 66 to an inoperative position, and releasingthe vacuum, the printed plate 16 can be removed for further processing.

To those skilled in the art to which this invention relates, manychanges in construction and widely diifering embodiments andapplications of the invention will suggest themselves without departingfrom the spirit and scope of the invention. For example, variousarrangements of the suction conduits, other than those illustrated, canbe employed with equal success. In addition, a moving rather than afixed light element might be employed (axial or curved) withoutappreciably varying the principles of operation. Accordingly, it shouldbe understood that the disclosures and description herein are purelyillustrative and are not intended to be in any sense limiting.

We claim:

In an apparatus for exposing a curved printing plate to adistortion-free light image, a curved plate holder, a flexible resilientblanket adapted to overlay said plate holder, said resilient blanketincluding wafile-like protuberances and passages on the inner surfacethereof, conduit means in said plate holder in communication with saidpassages, a source of suction being connected to said conduit means,said blanket having a transparent insert adapted to register with saidplate, and a curved light source concentrically positioned with respectto'said curved plate holder, whereby a photographic negative can bepositively held between said blanket and plate in a position of perfectregistry with said plate.

References Cited in the file of this patent UNITED STATES PATENTS607,648 Schwarz July 19, 1898 2,679,198 Hommel May 25, 1954 s d I

